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<html lang="zh-cn">
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        <title>小图标与文字垂直居中对齐</title>
        <style>
            *{padding:0;margin:0;}
            img{display:inline-block;width:19px; height:19px;vertical-align: middle;}
            .close-btn{background:red;color:#fff;height:19px;line-height:19px; padding:13px 0; width:120px;border-radius:5px;text-align:center;}
            span { display:inline-block; line-height:19px;vertical-align: middle;}
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    <body>
        <div class="close-btn">
          <img src="http://s1.mi.com/m/images/20151028/top-x.png">
          <span>关闭</span>
        </div>
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